In the field of distribution of fuel gas for its various uses, such as heating of environments, cooking of food, or industrial and professional uses, a very widespread solution is to resort, in the case where it is not possible to reach the place of use via the conventional natural-gas pipes, to installation of an LPG (Liquid Petroleum Gas) tank of suitable dimensions for the consumption levels envisaged by the user. The LPG gas tank, which, according to the modalities of installation, may be of an above-ground type or of a buried or underground type, is installed in a suitable position in the proximity of the user system to be supplied.
The gas tank may have a variable capacity roughly of between 1000 and 13000 liters, and in general needs to be refueled with a certain frequency in relation to the consumption levels.
For this purpose, the tank is equipped with a filling valve, in turn provided inside with a suitable non-return device, which prevents, in normal operating conditions, exit of the gas from the tank. The filling valve is opened automatically by the pressure of the LPG entering the tank only during the refueling operations that are performed by means of purposely designed tankers equipped with a pump, a flowmeter, a hose for transfer of the LPG, and a suitable refueling filler to be connected to the filling valve itself. In order to prevent refueling of the tank with gas by non-authorized subjects and other possible tampering, the filling valve is generally protected by a system that prevents access thereto, for example a simple lock or mechanical padlock that prevents connection of the filler.
Known, for example from the document No. DE202007008748, are solutions in which the gas tank is associated to a control module with an electromagnetic actuator that opens and closes the valve of the tank. The control module, via wireless communication with a control terminal, can govern opening of the valve.
The aforesaid system requires a specific electrical supply for operation of the control module and of the electromagnetic actuator. This electrical supply, installed on the filling valve, in the case of use of gases such as LPG, in a potentially explosive environment (ATEX 0) and, in the case of installation on tanks of a buried type, even in an environment that is potentially subject to flooding, is problematical to implement in a wired mode, whereas the use of batteries, in addition to the conditions referred to above (ATEX 0), presents the known drawbacks of limited battery life and reliability.